Avaliação do pico de pressão e da freqüência respiratória durante o uso de balão auto-inflável em um modelo de pulmão neonatal

Abstract

Ventilation rates achieved with the self-inflating bag were adequate in approximately 80% of pressure curves analyzed, but the physicians were unable to provide ventilation with minimal pressure variation, producing pressures that diverged from those defined by the neonatal resuscitation training course in 70% of the curves. This was irrespective of whether they were ventilating the lung model analogous to preterm or full term infant lungs.

An Evaluation of Peak Inspiratory Pressure, Tidal Volume, and Ventilatory Frequency During Ventilation With a Neonatal Self-Inflating Bag Resuscitator

“…We also found that nearly half of the participants delivered breaths at insufficient rates (Ͻ 40 breaths/min), in contrast with the findings by Rezende at al, 17,18 who showed good adequacy for f. This discrepancy is possibly due to differences in the volunteer population. Rezende et al 17,18 studied a small group of experienced physicians, whereas we studied a larger sample of subjects from 5 different professions who work with neonatal intensive care, with variable experience in resuscitation.…”

“…18 Both studies showed wide variability of delivered pressures and volumes, which frequently exceeded standard values for safe ventilation. 17,18 The present study shows that the high variability does not seem to be an artifact due to restricted sample size, because it was still observed even with a considerably greater number of volunteers (n ϭ 172). This is in agreement with the results of Roehr et al, 25 in which high variability of PIP (2.7-58.9 cm H 2 O) and V T (1-14.6 mL) was observed in a sample of 120 volunteers during ventilation of a neonatal mannequin with a self-inflating bag.…”

“…Rezende et al evaluated PIP, V T , and f, during ventilation with self-inflating bag in an analogue neonatal lung model, 17 as well as in term and preterm newborn sheep. 18 Both studies showed wide variability of delivered pressures and volumes, which frequently exceeded standard values for safe ventilation.…”

“…2 There is evidence that the ventilatory parameters delivered with this device may be influenced by several factors such as circuit con-figuration and brand, 4,5 the use of 1 or 2 hands to ventilate, 4,6-11 and operator's hand size, 4,7,12 profession, 6,13 and experience. 14 This may cause high variability of the absolute values of these parameters, 11,[15][16][17][18] causing delivery of either excessive or insufficient values. In the former case the risk for pulmonary injury (barotrauma and volutrauma) is increased, and in the latter there is a higher risk for hypoventilation.…”

É preciso repensar o conceito da ventilação manual com balão autoinflável em recém-nascidos

“…Isso resulta em lesão pulmonar por vários mecanismos, incluindo a exposição a elevadas concentrações de oxigênio, o atelectrauma e o volutrauma (3) . Neste sentido, os resultados publicados por Zaconeta et al (4) nesta edição da Revista Paulista de Pediatria têm o mérito de acrescentar mais informação a este assunto produzida por um grupo com tradição em pesquisa nesta área (5,6) . Um dos pontos fortes do trabalho é o estudo de uma população pouco avaliada na literatura pediátrica: profissionais não-médicos que atuam na linha de frente das emergências ocorridas com crianças fora do ambiente hospitalar.…”